This book presents mechanisms, protocols, and system architectures to achieve end to end Quality of Service (QoS) over heterogeneous wired/wireless networks in the Internet. Particular focus is on measurement techniques, traffic engineering mechanisms and protocols, signalling protocols as well as transport protocol extensions to support fairness and QoS. It shows how those mechanisms and protocols can be combined into a comprehensive end to end QoS architecture to support QoS in the Internet over heterogeneous wired/wireless access networks. Finally, techniques for evaluation of QoS mechanisms such as simulation and emulation are presented. This book is aimed at graduate and post graduate students in Computer Science or Electrical Engineering with focus in data communications and networking as well as for professionals working in this area.